Musnad Ahmad 2:280

Muhammad ibn Ja'far narrated to us, Shu'bah narrated to us, he said: I heard Abu Jamrah al-Duba'i narrating from Juwayriyah ibn Qudamah, he said: I performed Hajj and came to Medina in the year in which Umar was struck. He said: He delivered a sermon and said: "I saw as if a red rooster pecked me once or twice" — Shu'bah was the one who doubted. And it was of his affair that he was stabbed. Then he gave permission for the people to enter upon him. The first to enter upon him were the companions of the Prophet, may Allah bless him and grant him peace, then the people of Medina, then the people of al-Sham, then he gave permission to the people of Iraq. I entered among those who entered. He said: Every time a group entered upon him, they praised him and wept. He said: When we entered upon him, he had bound his stomach with a black turban, and the blood was flowing. He said: We said: "Advise us." He said—and no one asked him for a testament other than us—: "You must adhere to the Book of Allah, for you will never go astray as long as you follow it." We said: "Advise us." He said: "I advise you regarding the Muhajirun (Emigrants), for the people will increase and they will decrease. And I advise you regarding the Ansar (Helpers), for they are the branch of Islam to which it took refuge. And I advise you regarding the Bedouins, for they are your origin and your substance. And I advise you regarding the people of your covenant (Dhimmah), for they are the covenant of your Prophet and the provision for your dependents. Rise and leave me." He said: He did not add anything to these words for us. Muhammad ibn Ja'far said: Shu'bah said: Then I asked him after that, and he said regarding the Bedouins: "And I advise you regarding the Bedouins, for they are your brothers and the enemy of your enemy."